Device for charging a capacity



Feb. 19, 1952 1-. w. WILLEMSE 2,586,589

DEVICE FOR CHARGING A CAPACITY Filed Jan. 4 1951 THEO WILLEM WILLEMSE AGENT Patented Feb. 19, 1952 UNITED STATES P TENT; OFFICE DEVICE FOR-CHARGING A CAPACITY Theo Willem Willemse, Ei'ndhoven, Netherlands, assignor to Hartford National Bank and Trust Company, Hartford, Conn, as trustee Application J anuary 4, 1951, Serial No. 204,301 In the Netherlands January 19, 1950 The present invention relates to devices "for charging a capacity.

' In the copending patent application Serial No. 144,367 filed February 15, 1950 there is described and claimed a device for charging a capacity from which energy is derived discontinuously. Said. device comprises meansv which stop the charging ofv the capacity automaticallywhen the voltage of the capacity has reached a given value and which subsequently'do not absorb any further energy. In one embodiment, thedevice comprises a converter, which, if fed by direct current of low voltage, supplies directcurrent: of increased voltage which is suitable for charging a capacity, The device comprises a relay having two coils and two switches-mechanically coupled and op erative in the same sense, one coil-,the energizing coil, shunting the input terminalsof the converter and being adapted to be connected by way of one switch to the source of supply, and the second coil, the compensation coil, being connected by way of the second switch and a spark gap connected in series therewith to the output terminals of the converter, the compensation coil,

when sparking-over occurs, counter-acting the energizing coil, which keeps the two switches closed, in such manner that the switches are opened.

The device is again switched-in by means of an operating switch connected in parallel to the switch of the relay through which the energizing coil is adapted to be connected to the source of supply. I

The object of the invention is to ensure that the device is again switched-in automatically.

According to the invention, the output terminals of the converter are connected to a circuit comprising the series-connection of a condenser, .designated as a reswitching-in condenser and a further coil, designated as a reswitching-in coil, of the relay which is connected in such manner that the relay is closed when the capacity suddenly discharges.

In one preferred embodiment of the invention, the compensation coil is also used as the reswitchlng-in coil.

Provided in series with the reswitching-in coil may be a change-over switch which in the open 7 'cuit which does not form part of the compensation circuit.

the use of a gaseous discharge tube, which serves as. a flash-light source for photographic exposures. The capacity I is charged with direct current to a high voltage of, for example, some thousands of volts with the use of a converter 3, which may be connected by way of an operating switch Ate a direct current source 5 of low voltage, for example a dry battery. I

Connected in parallel to the input terminals Ofthe converteris an energizing coil '6 of a relay; the armature l of which operates two switches 8 and 9. 'The'switch 8 is connected in parallel to the operating switch 4. Closure of the switch 4 acts to connect the input terminals of the converter to'the battery 5, so that the charge' of the capacity commences. At the same time, the ener izing coil 6 is connected to the battery. As a result, the armature l of the relay moves in the direction of the single arrow, closing the switches 8 and 9. The latter keep closed even after opening of the operating switch 4 since the coil 6 is invariably connected to the battery by the closed switch 8. The input terminals of the converter are now also connected through switch 8 to the battery, so that the charging of the capacity continues.

The relay furthermore comprises a winding Ill, which is connected in series with a spark gap II, the closed switch 9 and a resistance I2 to the output terminals of the converter. The seriescombination of the coil Ill, and the spark gap H is shunted by way of a condenser 13 and a variable resistance l4 connected in parallel therewith. As soon as the voltage across the capacity has reached a value at which sparking-over occurs, the winding I0 is traversed by a current which causes the armature to move in the .direction of the double arrow against the action of the coil 6. Thus, the switches 8 and 9 are opened and keep open until the armature l of the relay is again moved into the closing position.

According to the invention, the relay is again switched-in automatically upon each sudden discharge of the capacity by means of a circuit comprising the coil I0 and a condenser l5 connected through the coil l0.

in series therewith. When the capacity I is discharged the condenser I 5 also discharges, the coil l0 being traversed by a current of such direction that the armature I of the relay is moved in the direction of the triple arrow so that the switches B and 9 are closed. The energizing coil 6 and also the input terminals of the converter 3 are then again connected to the battery 5 by the switch 8. The capacity I is subsequently recharged until a sharp discharge occurs across the gap II. It will be evident that the use of the coil In both for the automatic switching onand switching off constitutes a material simplification since otherwise the use of separate coils would be required for the two switching movements.

Provided between the spark gap II and the condenser I5 is a change-over switch IF, the countercontacts of which are connected to the two extremities of the coil ID. The coil I0 is switched off in the dotted position of the changeover switch [6, so that automatic reswitching-in does not take place. Since the change-over switch in the dotted position is connected'to a point of potential substantially equal to that in the reswitching-in position, current substantially I denser I5 of the reswitching-in circuit, that is to say in that portion of the reswitching-in circuit' which does not coincide with any part of the compensation circuit. In the absence of resistance l1, the switching-on current pulse occurring upon breakdown of the spark .gap I'I could flow through the series-connectionof the instead of Furthermore, in the absence of resistance H, the current pulse .for re condenser I5 and the capacity I switching-in, originatin from the condenser i5,

4 decoupling element between the compensation and reswitching-in circuits.

What I claim is:

1. Apparatus for charging a capacity from which energy is withdrawn discontinuously comprising a source of direct voltage constituted by a low voltage supply and a'converterwhose input terminals are connected to said supply and whose output terminals are connected to said capacity to produce a relatively high charging voltage therefor, a relay including first and second coils for actuating first and second normally open switches, said first coil when energized causing said switches to close and said second coil when 3? simultaneously energized counteracting the effect of said first coil whereby said switches reopen, means interposing said first switch between said low voltage supply and the input terminals of said converter, a spark-gap connected through second coil in series with said second switch across the output terminals of saidconverter,

said gap being rendered conductive when said capacity attains a predetermined value, a reswi-tching-in coil for said relay; a: condenser, and

a circuit connecting said condenser in series with said reswitching-in coil across the output terminal of said converter, said reswitching-in coil being energized upon sudden discharge of said capacitythereby to close said relay.

2. Apparatus, as set forth in claim 1, wherein said second coil acts also as the reswitching-in No references cited. 

